This invention relates to the production of organic solvent-free capsules containing a fabric antistat/softener material and a process for so producing. The present invention additionally relates to a liquid fabric conditioning composition containing the substantially organic solvent-free capsules.
In the conventional home laundering process, soiled fabrics are subjected to cleaning with a detergent composition in the main wash cycle and rinsing with water in the final cycle. Optionally, during the rinsing cycle a fabric conditioning composition is added. Such compositions contain a fabric softener or fabric antistat material for imparting to the rinsed fabrics' softening and antistat properties. The rinsed fabrics are oftentimes, thereafter, dried in an automatic clothes drier.
A long-standing problem has been how to deliver the fabric conditioning agents during the rinse cycle and have the benefits retained after the drying operation. It is difficult to deliver the fabric conditioning agents to the fabrics from a dilute solution such as is encountered in a rinse cycle. Attempts have been made to improve the efficiency of conditioning agent fabric deposition during the laundering process. For example, U.S. Pat. No. 3,442,692 overcomes the problem of delivery to the fabrics by adding the conditioning agent to the automatic dryer.
Another problem has been the attainment of satisfactory antistat properties on the dried fabrics. A static electric charge develops on fabrics during the tumbling of the fabrics in a clothes drier. Such a charge is objectionable to the consumer because of difficulty it causes in sorting and folding of the dried fabrics. Conventional fabric softener delivered to the fabrics either in the rinse cycle or during the drying operation alleviates the problem of static electricity build up on the fabrics. However, it has been found that when the fabric softener is delivered in the rinse cycle, it hydrates with the water and partly leaves the surface to migrate to the inner portions of the fabric. Since the build up of static electricity occurs across the surface portions of fabrics, the most beneficial use of the fabric softener for antistat benefits would be if it would substantially remain on the surface portions.
Treatment of fabrics after the drying operation has also been attempted. For example, U.S. Pat. No. 3,870,542 teaches the treatment of fibrous articles with a composition containing microcapsules. The microcapsules contain a solvent and a fabric conditioning agent. The treatment process comprises applying the microcapsules to the fabric and thereafter breaking the microcapsules to release the solvent solution onto the fibrous article. Such a process is not conducive to home laundering situations. Moreover, the presence of the solvent causes odor problems and is costly.
It accordingly is an object of this invention to provide a fabric conditioning composition intended for use in a home laundering operation wherein a fabric antistat/softener material can be effectively and efficiently applied to fibrous articles.
Another object of this invention is to provide a liquid fabric conditioning composition adapted to be added during the rinse cycle of the washing process which is capable of providing fabric antistat/softener properties to rinsed fibrous articles.
Still another object of this invention is to provide organic solvent-free capsules containing a fabric antistat/softener material.
These and other objects will become apparent from the description which follows.
As used herein all percentages and ratios are by weight unless otherwise indicated.